Rabies: Of Mad Dogs (and Cats) and Englishmen

RABID KITTEN. There’s your phrase of the day. Try to work it into at least one conversation. I’m not touting some obscure punk band… no, there was nothing remotely entertaining about the infected kitten that bit me while I was working in Washington, D.C. Funny, I’d served in the Peace Corps in Africa and then trekked around India for three months—two of the most rabies-intensive parts of the world—with no problem at all, and then this unlikely suspect nailed me in one of our capital’s wealthiest neighborhoods.

You don’t see “rabid” and “kitten” together often, and not just because of the pervasive cuteness of catness on the Internet. Rabies can have a long incubation time, which means it’s likelier to show up among adult animals. I survived this close encounter with one of humanity’s most feared diseases because I’d been inoculated in the Peace Corps, and then followed up the exposure with another series of shots. Here’s a shout-out to Louis Pasteur and Pierre Paul Emile Roux, who developed the first rabies vaccine in 1885. Merci, messieurs! (Incidentally, Pasteur and Emile Roux knew rabies as la rage. Even diseases sound better in French.)

Rabies is fascinating—and fortunately, rare here in the U.S. It’s almost always fatal once serious symptoms begin to show. Before Pasteur and Emile Roux, the bite itself was virtually a death sentence. Even today, rabies kills 55,000 people a year worldwide, according to the World Health Organization, and 15 million every year get post-exposure shots like mine. The WHO says those shots save 327,000 lives annually. People get the shots because it’s impossible to diagnose rabies in humans before it’s progressed to a lethal stage. The number of people who have eversurvived full-blown rabies can be counted on your two hands, with several fingers left over.

Rabies is caused by a virus, nothing but a little packet of protein. It has the ability to travel up our nervous system, infect our big, complex mammalian brains, and completely alter our behavior, making us agitated, confused, and aggressive. (Too bad there’s no virus that turns human brains incurably mindful, generous, and kind.) Worse symptoms follow, including the classic “hydrophobia” (in times past, some people called the disease itself by this name), which torments the patient with a combination of desperate thirst, paralyzed throat and jaw muscles, and what looks like a bizarre aversion to water. The virus settles into the salivary glands, so a person or animal that bites another and spreads that virus-laden drool is sure to pass it on, like a real-life vampire. Another fiendishly clever evolutionary adaptation.

As for vampires—yes, bats (of the non-supernatural sort) are often to blame for rabies infections. We have bats in the Bay Area, and they’re natural reservoirs of the virus. You shouldn’t touch or pick up bats, dead or alive.

For a human to get rabies, the person must have contact with a rabid animal’s infected material, generally saliva, usually through a bite or scratch. The virus then takes days or months to travel up the peripheral nerves to the brain. The incubation time depends on where the bite and infection occurred: a bite on the foot may take six months to reach the brain, while a neck bite may take only a week or two. Once the virus is in the brain, causing clinical signs, death comes within ten days.

The unpredictable incubation time is why Britain and other rabies-free islands impose four- to six-month quarantines or blood-test requirements for entering animals. Fortunately, a pet owner fulfilling specific requirements for microchipping, vaccination, and certification can skip the long quarantine in many countries.

Such border hurdles are worth the trouble, medically, because dogs are by far the most common culprits among domestic animals for worldwide rabies infections (the WHO blames them for 99 percent of human rabies deaths). In the United States, though, cats are the most common domestic animals with rabies. It makes sense when you think about it: stray dogs are a lot less common here than they used to be, while feral cats are still plentiful. Among both cats and dogs, decreasing stray populations and increasing vaccination rates have cut rabies occurrences in the United States, resulting in only a handful of deaths per year.

Almost any wild or domestic warm-blooded animal can potentially get rabies, but only mammals can be vectors, those that spread the disease. Bats and skunks lead the list in California. Rabies is rare among small rodents (rats, squirrels, and chipmunks), possums, and lagomorphs such as rabbits or hares—so Monty Python’s killer rabbit must have gotten its terrorizing power from something else. Ditto for Jimmy Carter’s berserk swamp bunny.

Now you know why veterinarians and shelters are so rabid, so to speak, about vaccinating your pets. Post-exposure treatment for people is unpleasant, expensive, and scary (although shots are usually given in the arm, not the abdomen, despite what you may have heard). Your cat or dog, if it contracts the virus, won’t have a chance unless its shots are up to date. I don’t want to scare people, but rabies is present in our area. Four bats tested positive in San Francisco over the past year. Just last week, an eight-year-old girl named Precious finally left a hospital in Davis after a two-month battle with the disease. The culprit was a scratch from a feral cat. (Here at the SF SPCA, we vaccinate all feral cats in our trap-neuter-release program for rabies.)

It may be tempting to skip this vaccine for your companion animals, but don’t. Gambling with your health, and your animal’s health, is bad enough. But if your unvaccinated pet bites a person or another pet, it has to be quarantined for ten days. And if your unvaccinated pet is bitten by any other unvaccinated animal, domestic or wild, it must be considered exposed and will be quarantined for months.

Vaccination sets your mind at ease—or nearly so. Even after I got my shots after tangling with that rabid kitten, I was uneasy. A few months later, while working in my darkroom, I got frustrated and found myself, to my horror, biting the film. I grabbed a glass of water to see if I passed the hydrophobia test… whew, false alarm.